#1 hollowilbur shipper

The Wilbur in this AU is very much not a good person at first, but he still has his own issues and trauma going on. But because Duke doesn't know that much about Wilbur, he'll often be the one when they first get stuck in the house to play devils advocate for Wilbur and suggest giving him another chance. Every single time Duke does this, Wilbur takes advantage of it to do something annoying and shitty to either John, Holloway, or the whole group, and it messes them all up, but Duke misguidedly thinks Wilbur could change once they've been in the house for long enough.

Then he finds out about how Wilbur murdered his dad, and every single bit of good will Duke had for Wilbur initially gets thrown out the window. The way he finds out too is from an offhanded comment Wilbur makes during one of the room explorations and then it spirals from there as all four of them suddenly put the pieces together that Wilbur is in fact the one that killed Duke's dad way back when he'd first become Wiggly's right hand man. And this is a huge issue between the two of them, because Duke had a very strong connection to his dad as a kid.

After this happens Wilbur doesn't have anyone in the group he can really mess with or that will give him any sort of grace, so he stops and becomes much more reclusive. He'll say snarky mean comments but he won't do much, including interacting with them. For the most part none of them really notice or care all that much, until Duke notices it in a room where there's a lot of stuff related to Wiggly (haven't figured out the specifics of the Wiggly room).

And so later that night Duke and Wilbur end up actually talking because Wilbur accidentally woke Duke up cause of a nightmare he had. Duke hears a little bit about the relationship Wiggly and Wilbur had and how at this point from being in the house, Wilbur does actually want to change and be better, he just doesn't think he should get that chance.

And Wilbur asks Duke why he's even listening to him and letting him vent to him and being nice, especially since Duke knows Wilbur killed his dad and didn't seem very remorseful about it when it came up initially. Duke ends up saying this:

“I’m not being nice. I’m giving you grace. No one can expect you to change if you don’t at least get some grace.”

And so after that, Duke doesn't necessarily advocate for Wilbur's change, but he does provide opportunities for him to show he's willing to actually put in the effort to do so.

I don't think Duke ever fully forgives him for killing his dad, and he definitely doesn't immediately switch back after there conversation, but he waits and sees how Wilbur chooses to try and become better and then once he sees Wilbur be nicer and try to fix the wrongdoings he's done to John, Holloway, and Duke (showing remorse and sympathy for killing his dad), he slowly re-builds a better friendship with him.

Long winded explanation aside this is how I was thinking about that info and that bond between them-